Atomic Annie (M65 Atomic Cannon)
A Big Big Gun

The atomic shell used by Atomic Annie, designated W9, was just over 900 lbs and due to its weight and poor aerodynamics had a shorter range than a conventional shell. The replacement atomic shell, the W19, weighed only 600 lbs and could outrange its conventional cousin. One of the few remaining M65s, this one at the Nuclear Museum in Albuquerque.

The Army, back in the 1950s, claimed that the gun could be set up, loaded, and fired, all within twenty minutes, which seems difficult to believe. How fast they could move the unit after firing, to avoid incoming fire, is not mentioned. At the Nuclear Museum in Albuquerque.

Once lowered to the ground the M65 had the ability to rotate 360 degrees and could elevate its gun by fifty-five degrees. At the Nuclear Museum in Albuquerque.

Nuclear researcher Chuck Hansen wrote that the efficiency of the W9 in utilizing its uranium was poor–and quotes one unnamed source as describing its efficiency as “woeful.” The Navy and Air Force cited this inefficiency in the use of the expensive and difficult to make uranium as a prime objection to this weapon. This is the barrel of the original Atomic Annie, at Ft. Sill in Oklahoma.

This is the original “Atomic Annie,” which fired the nuclear shell in 1953. The cannon was mis-identified for ten years after the nuclear test and found its way to Germany while the backup cannon from the atomic test was mistakenly thought to be Annie. Located at Ft. Sill in Oklahoma.

Another view of the original Atomic Annie at Ft. Sill. When it fired the Grable test shot it missed the target (aiming for 500) by twenty-four feet (it was too high), too far west by eighty-six feet, and too far south by one hundred and thirty-seven feet. This is said to be accurate for a such a large gun, well within the “bulls-eye” for an atomic weapon.

Although most sources label this shell (at the Nuclear Museum in Albuquerque) as a W9, it may instead be the W9’s replacement, the W19, a smaller, lighter, and more aerodynamic projectile, with a longer range.

This is a nuclear artillery shell but not for the Atomic Annie. It took from 1945 to 1953 to shrink an explosive with the power of Little Boy down to the 280mm shell, and the miniaturization did not stop there. This shell, the M455 is the training shell for the nuclear version, the M455, and could be fired from a standard Army M109 self-propelled howitzer (still in use today). The M454 entered service in 1963 and was in inventory until 1992. Located at the Atomic Museum in Las Vegas.
Explosive Power
15 kt. with W9 or 15-20 kt. with W19 warhead
Hiroshima Equivalent Factor
1x to 1.3x
Dimensions
84 x 16 x 12 ft.
Weight
86.5 tons
Year(s)
1953-1963
Range
20 miles
Purpose
Impressive-looking nuclear artillery
Nukemap
NUKEMAP is a web-based mapping program that attempts to give the user a sense of the destructive power of nuclear weapons. It was created by Alex Wellerstein, a historian specializing in nuclear weapons (see his book on nuclear secrecy and his blog on nuclear weapons). The screenshot below shows the NUKEMAP output for this particular weapon. Click on the map to customize settings.

Videos
Click on the Play button and then the Full screen brackets on the lower right to view each video. Click on the Exit full screen cross at lower right (the “X” on a mobile device) to return.
Further Reading
- Wikipedia, Global Security, Nevada National Security Site.
- Two guns were sent to Nevada for the nuclear test, Able Annie and Sad Sack. Able Annie fired the atomic shell, thus becoming “Atomic Annie.” Soon after their identities were switched and for ten years Sad Sack was displayed as Annie while Annie while Ft. Sill attempted to locate the real Annie. It’s a popular story.
- When Annie was located in Germany it was brought back. On the way it rolled over in a tragic accident. Paul Jakstas worked on the recovery of an M65 cannon, in the same year that Annie would have been moved back to Ft. Sill. Reddit user double-dorrito has photos of crashed transporter vehicles, possible the same crash, taken by his grandfather.
- After Annie and Sad Sack, both prototypes, this cannon, at Fort Gregg-Adams (formerly Fort Lee) in New Jersey, was the first one off the production line. This cannon is highlighted by US Army Corp of Engineers as well.
- Tom Lambert was an Army private who witnessed the test of the M65 cannon–and then was ordered, along with his fellow soldiers, to walk toward ground zero. His story is well worth reading, written by his son, Tim. This interview, with both Tom and Tim Lambert, appears to be the basis of that article. Donald E. Bennet was there, too.
- Paul Gaertner has an entire site dedicated to the M65 Atomic Cannon.
- The cannon was designed by naval ordinance engineer Robert M. Schwartz and his work is profiled at Coffee or Die.
- Family members of soldiers who worked with these guns sometimes post images to Reddit. Others post photos of the M65 rolling through Washington, DC as part of Eisenhower’s inaugural parade.